{"slug":"era5-hourly-data-on-pressure-levels-from-1979-to-present","name":"reanalysis-era5-pressure-levels","id":"eu.copernicus.climate.reanalysis-era5-pressure-levels","type":"dataset","rich_abstract":"\u003cdiv class\u003d\u0027abstract-text\u0027\u003e\n \u003cp\u003e\u003cstrong\u003eERA5\u003c/strong\u003e is the fifth generation ECMWF atmospheric reanalysis of the\nglobal climate. Reanalysis combines model data with observations\nfrom across the world into a globally complete and consistent dataset\nusing the laws of physics. This principle, called data assimilation,\nis based on the method used by numerical weather prediction centres,\nwhere every so many hours (12 hours at ECMWF) a previous forecast\nis combined with newly available observations in an optimal way to\nproduce a new best estimate of the state of the atmosphere, called\nanalysis, from which an updated, improved forecast is issued.\nReanalysis works in the same way, but at reduced resolution to allow\nfor the provision of a dataset spanning back several decades.\nReanalysis does not have the constraint of issuing timely forecasts,\nso there is more time to collect observations, and when going further\nback in time, to allow for the ingestion of improved versions of\nthe original observations, which all benefit the quality of the\nreanalysis product.\u003c/p\u003e\n\u003cp\u003eThe assimilation system is able to estimate biases between observations\nand to sift good-quality data from poor data. The laws of physics\nallow for estimates at locations where data coverage is low, such\nas for surface temperature in the Arctic. The provision of estimates\nat each grid point around the globe for each regular output time,\nover a long period, always using the same format, makes reanalysis\na very convenient and popular dataset to work with.\u003c/p\u003e\n\u003cp\u003eThe observing system has changed drastically over time, and although\nthe assimilation system can resolve data holes, the initially much\nsparser networks will lead to less accurate estimates. For this\nreason, ERA5 includes an uncertainty estimate that provides guidance\non where products are expected to be more and where less accurate.\u003c/p\u003e\n\u003cp\u003eWhen complete, ERA5 will contain a detailed record of the evolution\nof the global atmosphere from 1950 onwards with a total size of\nabout 9 Petabytes. ERA5 will replace the ERA-Interim reanalysis,\nwhich is now 10 years old.\u003c/p\u003e\n\u003cp\u003eAlthough the analysis procedure considers chunks of data in a window\nof 12 hours in one go, ERA5 provides estimates for each hour of the\nday, worldwide. This is made possible by the 4D-Var assimilation\nmethod, which takes account of the exact timing of the observations\nand model evolution within the assimilation window. This hourly\noutput resolution is quite an improvement with respect to ERA-Interim,\nand provides a more detailed evolution of particular weather events.\u003c/p\u003e\n\u003cp\u003eVariables are produced at the surface and on model levels but are\nalso interpolated to three other level types: pressure levels,\npotential temperature levels and one potential vorticity level. In\norder to make data access more manageable, the ERA5 dataset has\nbeen split into several records.\u003c/p\u003e\n\u003cp\u003eThe present record is the \"ERA5 hourly estimates of variables on pressure levels\".\u003c/p\u003e\n \u003cp\u003e\u003ci\u003eMore details about the product are given in the Documentation section.\u003c/i\u003e\u003c/p\u003e\n \n \u003cp\u003e\u003c/p\u003e\n \u003ctable class\u003d\"abstract-description abstract-table\"\u003e\n \u003ctr\u003e\u003cth colspan\u003d\"2\"\u003eDATA DESCRIPTION\u003c/th\u003e\n \n\u003ctr\u003e\u003cth\u003eHorizontal coverage\u003c/th\u003e\u003ctd\u003eGlobal\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003cth\u003eHorizontal resolution\u003c/th\u003e\u003ctd\u003e\u003cp\u003eReanalysis: 0.25°x0.25°\u003c/p\u003e\n\u003cp\u003eMean, spread and members: 0.5°x0.5°\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003cth\u003eTemporal coverage\u003c/th\u003e\u003ctd\u003e1979 to present\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003cth\u003eTemporal resolution\u003c/th\u003e\u003ctd\u003eHourly\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003cth\u003eFile format\u003c/th\u003e\u003ctd\u003eGRIB\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003cth\u003eData type\u003c/th\u003e\u003ctd\u003eGrid\u003c/td\u003e\u003c/tr\u003e\n\u003c/table\u003e\n\n \u003cp\u003e\u003c/p\u003e\n \u003ctable class\u003d\"abstract-variables abstract-table\"\u003e\n \u003ctr\u003e\u003cth colspan\u003d\"2\"\u003eMAIN VARIABLES\u003c/th\u003e\n \u003ctr\u003e\u003cth class\u003d\u0027variables-name\u0027\u003eName\u003c/th\u003e\u003cth class\u003d\u0027variables-units\u0027\u003eUnits\u003c/th\u003e\u003c/tr\u003e\n \n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eDivergence\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003es\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eFraction of cloud cover\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003e(0 - 1)\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eGeopotential\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003em\u003csup\u003e2\u003c/sup\u003e s\u003csup\u003e-2\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eOzone mass mixing ratio\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003ekg kg\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003ePotential vorticity\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003eK m\u003csup\u003e2\u003c/sup\u003e kg\u003csup\u003e-1\u003c/sup\u003e s\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eRelative humidity\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003e%\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eSpecific cloud ice water content\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003ekg kg\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eSpecific cloud liquid water content\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003ekg kg\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eSpecific humidity\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003ekg kg\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eSpecific rain water content\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003ekg kg\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eSpecific snow water content\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003ekg kg\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eTemperature\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003eK\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eU-component of wind\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003em s\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eV-component of wind\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003em s\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eVertical velocity\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003ePa s\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003ctr\u003e\u003ctd class\u003d\u0027variables-name\u0027\u003eVorticity (relative)\u003c/td\u003e\u003ctd class\u003d\u0027variables-units\u0027\u003es\u003csup\u003e-1\u003c/sup\u003e\u003c/td\u003e\u003c/tr\u003e\n\u003c/table\u003e\n \u003c/div\u003e\u003cp\u003e\u003c/\u003e\u003cp\u003e\u003csmall\u003e\u003ci\u003eRecord updated 2019-02-15 17:20:02 UTC\u003c/i\u003e\u003c/small\u003e\u003c/p\u003e","terms":["licence-to-use-copernicus-products"],"wms_sample":null}